1. Field of the Invention
This invention relates to fume hoods for laboratories and the like which have open front cabinets closed by transparent lift sash that are inclined inwardly to increase interior visibility and specifically this invention relates to laboratory fume hoods having open front cabinets with waist high floors and upright lift sash windows above the floor controlling airflow which are inclined inwardly and have outwardly inclined transparent panels above the sash openings.
2. Description of Prior Art
Heretofore known laboratory fume hood cabinets with waist or desk (3-3-1/2 feet) high floors or article receiving platforms have had vertical lift sash closing and giving access to the cabinet with the front of the cabinet above the sash opening being closed by opaque front vertical panels. The vertical lift sash was raised behind the panels, opening the front of the cabinet below the panels and blocking airflow behind the panels. This vertical sash, even though it had a transparent window, reflected outside light and did not give clear vision to articles on the floor in the cabinet. The opaque top front panels of the cabinet blocked lighting of the cabinet from exterior light sources and prevented clear vision to articles in the upper part of the cabinet.
It would therefore be an improvement in this art to so mount the lift sash of fume hoods to increase interior visibility and decrease required lift space.
It would be a further improvement to increase the lighting of the fume hood cabinet from outside sources without adding equipment and allow vision to entire interior of the cabinet.
A specific improvement is tilting lift sash of fume hoods inwardly about 5 to 20 degrees from vertical.